Processing of malt for preparing a beverage

ABSTRACT

In a method for preparing a beverage, a dough—which has been prepared from malt flour and water=13 is diluted with water to a mixture of malt flour in water, the diluted mixture containing 11 to 45 wt. % malt flour, based on the total weight of the mixture. Also described are intermediate products and beverage obtainable by a method as described. The method has been found particularly suitable for preparing alcohol-containing beverages.

The invention relates to a method for preparing a beverage. Theinvention further relates to intermediate products and a beverage whichare obtainable by means of a method according to the invention.

Malted cereals are used in the preparation of all types of beverages.Thus, for instance, they are used in kvass, a fermented nonalcoholicbeverage. In the abstract of Russian application RU 2 177 501 it isdescribed that a dough is prepared which contains 3-10% malt and diverseother ingredients, such as boiled potatoes, rusk crumbles, bakery yeast,rye flour, sugar, and flavorings. This mixture is diluted in a ratio of1:12 to 1:5 and fermented.

Also for brewing alcohol-containing beverages based on cereal, such asbeer, the cereal, in particular barley, is generally malted. The malt issubsequently ground to malt flour, which is then dispersed in excesswater. This mixture is subsequently processed to wort, which is in turnprocessed to a beverage, for instance by means of fermentation.

It has been found that in such a brewing process by no means all of thepolymers, such as starch, cell wall components, proteins, and sugarsoriginating from the cereal, are decomposed. Insufficient decompositionof such components proves to be able to lead to, inter alia, turbidityand gel formation, which can, in turn, lead to product and/or time lossas a result of filtration problems during brewing. It can also adverselyaffect the stability and/or the quality of the final product, inparticular of beer.

Through the filtration problems in conventional processes, use istherefore generally made of coarsely ground malt grits, in whichrelatively large pieces of chaff are still present, which serve as aidfor limiting filtration problems. The use of coarsely ground malt grits,however, is not always sufficient to effectively solve the filtrationproblem and also has drawbacks with respect to the efficiency of thebeverage preparation process.

It is an object of the invention to provide a novel method for preparinga beverage based on a cereal, in which at least one of theabove-mentioned drawbacks is removed or at least reduced.

It has now been found that this object is achieved by processing maltflour in a specific manner.

The invention therefore relates to a method for preparing a beverage inwhich a dough is prepared from malt flour and water and the dough isthen diluted with water to a mixture, in particular a dispersion, ofmalt flour in water.

The mixture can be further processed in a manner conventional for thebeverage preparation, for instance beer preparation. Among typicalprocessing steps of which one or more can be carried out are filtering,extracting, heating, cooling, adding additives, and fermenting.

The term water is used herein in a general sense. This term particularlycomprises distilled water, demineralized water, mains water, and ingeneral aqueous solutions suitable for use in consumption goods, inparticular beer and other beverages.

Malt flour is a flour which, at least to a substantial part, consists ofground, completely and/or partly germinated cereal. Besides, the maltflour may optionally contain ground, non-germinated cereal.

The dough is a kneadable mixture, which substantially contains maltflour and water. The malt flour is preferably finely ground malt flour,so that no relatively large pieces of chaff are present in the flour.

Optionally, the flour may first be separated by a sieving process (forinstance by means of a sieve having a mesh in the range of 112-1000 μm,preferably a mesh in the range of 112-475 μm) into a coarse part (forinstance with at least substantially particles having a particle size ofmore than 1000 μm, or of more than >475 μm) and a fine part. The finepart preferably consists at least substantially of parts having aparticle size of less than 1000 μm, very preferably of less than 475 μm,particularly preferably of less than 112 μm.

The fine part is preferably used for preparing dough having improvedconsistency.

If desired, the coarse part may be added again to the dough or dilutedmixture at a later stage with a view to a good natural filtration effectof malt grits. It is observed that the dough compositions mentionedlower down preferably relate to the situations in which no coarse partshave been added.

One or more additives licensed for foodstuffs may be added as well, forinstance one or more additives which favorably affect the consistency ofthe dough, such as, for instance, common salt (NaCi). Common salt ispreferably present in the dough in a concentration of 0-3 wt. % (basedon the total weight of dry flour), in particular in a concentration of0.025-2 wt. % (based on the total weight of dry flour).

The dough preferably has a consistency of at least 100 BrabenderFarinograph units, more preferably at least 150 Brabender Farinographunits. Particularly good results have been achieved with a dough havinga consistency of at least 300 Brabender Farinograph units. The BrabenderFarinograph units as meant herein are the values obtainable by means ofmeasurement on a Farinograph® E, by means of ISO 5530-1.

The content of malt flour and water may vary depending on the use, otheringredients and the type of malt flour. On the basis of general expertknowledge and of what is described herein, the skilled worker will knowto select a suitable ratio of constituents to achieve a goodconsistency. In practice, the dough will usually consist to at least 45wt. % of malt flour. Very good results have been achieved with a maltflour content of at least 50 wt. % malt flour, in particularapproximately 55-65 wt. % of malt flour.

With respect to the amount of water very good results have been achievedwith a water content of maximally 45 wt. %, in particular with a watercontent in the range of 35-44 wt. %.

The weight percents (wt. %) herein relate to the total weight of therespective composition, unless explicitly mentioned otherwise.

It has been found that by means of a method according to the invention amore effective conversion of starch to sugars takes place, and inparticular to fermentable sugars. A method according to the inventioncan also contribute to a better decomposition of other constituents ofthe malt flour, for instance of proteins. Since the sugar contentdirectly relates to the yield of alcohol when the mixture is fermented,the invention offers the possibility of generating a higher yield of analcohol-containing beverage, such as beer.

A method according to the invention has the economic and environmentaladvantages that no excess water need be used, which can also result intime and energy saving because no excess water, therefore, need beheated, cooled and/or removed.

Besides, a method according to the invention offers the advantage thatno or at least fewer clogging problems occur during the furtherprocessing of the diluted mixture of malt flour in water and/or of wortand/or beverage (in particular beer) which have been prepared from themixture. In particular, clogging of filters and the like can beprevented or can at least be reduced. It is assumed that as a result ofthe increased conversion of starch to sugars undesired gel formation ofthe above-mentioned polymers, such as starch and/or proteins, in thediluted mixture, the wort and/or the beverage is reduced or evencompletely prevented. Such gels can actually lead to clogging offilters.

Through the good filtration characteristics, it is possible to processthe malt flour in an economically attractive manner and to prepare abeverage without making use of chaff as filtering aid, even though it ispossible, in principle, to use chaff as such in a method according tothe invention. The chaff content in the malt flour and the dilutedmixture (dispersion) may therefore be low, which can, for instance,offer advantages with respect to the taste and stability.

An additional advantage of a method according to the invention is thatbecause of the favorable effects on the filtration characteristics it isnow possible to prepare a more concentrated mixture (dispersion) and, inparticular, a more concentrated wort than hitherto usable for furtherprocessing to beverage. Thus, for instance, in the beer preparation itis conventional to use wort having a content of 10-20 wt. % of maltflour constituents. The invention renders it possible to favorably usewort having a content of more than 20 to 40 wt. % or more of malt flourconstituents. As a result thereof, the yield of final product (such asbeer) can be considerably increased.

A particular aspect of the invention further is that use can efficientlybe made of finely ground malt flour, starting from flour bodies or maltgrits, the chaff, if present, having been finely ground as well. The useof finely ground malt flour is desired because a higher yield of finalpro ducts can thus be obtained.

In principle, the invention can be applied to any type of malt flour.Very suitable is barley malt flour, even though other malt flours arealso suitable.

An additional advantage of the invention is that the quality of the rawmaterial for the malt flour is less critical to obtaining a good yieldand quality of the final product. Thus, for instance, the inventionoffers the possibility of effectively and economically attractivelymaking use of malt flour prepared which has been prepared from cerealconsisting to a substantial part of, for instance mainly, of glassygrains (so-called “stealy” cereal), non-germinated grains, incompletelygerminated grains and/or grains of traditional “non-malt” barley orother cereals which do not (completely) meet the requirements for thetraditional specific brewing barley. In respect of, for instance, cerealwhich was previously found unsuitable for brewing a beverage, such asbeer, because it did not meet the traditionally required specifications(as laid down in, for instance, the EBC (European Brewing Convention)standards) in the field of protein content, extract yield, kolbach,friability, germ capacity, yeastability etc. it has been found that bymeans of the invention it is usable for brewing a beverage, such asbeer.

When malt flour, and in particular malt flour of relatively low quality,is processed in a conventional method (by adding excess water), itgenerally turns out that the starch is decomposed only in a relativelysmall degree. By first kneading the malt flour to a dough, the starchproves to be able to be decomposed in a greater degree. It is assumedthat kneading leads to breaking a protective layer which protects thestarch bodies in the flour from factors promoting starch decomposition,such as specific enzymes. Thus, for instance, it could be so that thestarch is protected by a protein matrix which has deposited on the flourbodies during the formation of the seed. Besides, in particular forglassy grains, the low water uptake capacity could adversely affect thedecomposition of starch. Moreover, it is not impossible that throughmodifications in the molecular structure of the starch hydrolases showless activity for the starch in glassy grains.

Previous to the dilution with water, the dough is preferably kneaded forsome time. The kneading temperature, kneading time, and the kneadingpower may be selected within broad limits. The skilled worker will knowto determine a suitable temperature, time and power on the basis of thedesired degree of conversion of starch and the nature of the malt flour.

Very suitable is a method in which the dough is kneaded for at least minor mechanical energy is supplied to the dough in another manner. Theupper limit is not particularly critical and may, for instance, be twoor more hours. In practice, a shorter kneading time will already besufficient to obtain a favorable effect. Very good results have, forinstance, been achieved with a kneading time of 30-45 min.

The supplied mechanical energy, such as the kneading energy suppliedduring kneading, is preferably at least 1 kJ/kg/min dough. The upperlimit is not particularly critical. Very good results have, forinstance, been achieved with a mechanical energy (in particular kneadingenergy) in the range of 1 to 100 kJ/kg/min.

By kneading, not only the dough components are mixed to a homogeneousmass, but it is further assumed that, by kneading, polymer constituents,such as proteins, starch, and cell walls, are better and more rapidlyaccessible to decomposition by enzymes and that, accordingly, theundesired gel formation already mentioned above can be reduced or evenprevented, in particular such gel formation caused by cell wallcomponents, such as glucanes and pentosanes. Moreover, proteins andstarch can be more rapidly hydrated. Besides, it has been found thatkneading has a favorable effect on the decomposition of proteinstructures, such that backformation of the protein structure can beprevented.

It is assumed that decomposition of the macromolecular proteinstructures is favorable for the efficiency of the modification of themalt. Kneading may, for instance, very suitably be carried out in amixer, in particular a mechanical mixer, for instance in a Z-blademixer, a pin mixer, an extruder or an ultrasonic apparatus.

Besides by kneading, it is possible, in principle, to differently supplyenergy to the dough, for instance through a heat treatment. Particularlyconsidered here is a heat treatment at a temperature of approximately25-60° C., preferably for a time sufficiently long to supply theabove-mentioned inserted energy to the dough. The skilled worker willknow to determine a suitable period of time by way of routine, dependingon factors such as the temperature, the batch size, and the heatcapacity of the dough.

In practice, it is preferred to carry out the supply of mechanicalenergy (as by kneading) and/or the dilution at a temperature of 15-60°C. Preferably, the temperature is lower than 50° C. At a temperaturewithin the range of 20-45° C., it has been found that a very gooddecomposition of compounds and/or structures which adversely affect thefiltration takes place. Very good results have been achieved at atemperature of approximately 25-35° C., for instance circa 30° C.

After supplying the energy (as by kneading), the dough is diluted withwater. The dilution with water may occur by adding water to the dough orby adding dough to the water. The water is preferably gradually admixedwith the dough while substantially continuously mixing (for instancekneading and/or stirring) so that the formation of an insoluble doughball in water is prevented. Preferably immediately after kneading, thedough is further diluted with water until the desired consistency forthe intended use has been obtained, for instance until a consistencyconventional for wort.

Preferably, the dilution is carried out until a content in the range of11 to 45 wt. % malt flour constituents based on the total weight of themixture. Very preferably, the content of malt flour constituents is morethan 20 wt. % and less than 40 wt. %.

A method according to the invention is particularly suitable forpreparing a fermented beverage, in particular beer. The further steps ofprocessing the diluted mixture (dispersion) of malt flour in water maybe carried out in a manner known in the state of the art. The dilutedmixture may, for instance, be processed to wort and then be fermented.Previous to the fermentation, one or more steps conventional for thepreparation of beverage may optionally be carried out, such asextracting, filtering, diluting, adding hops, boiling wort, etc.

The invention also relates to a dough obtainable by means of theinvention and to a dough which at least substantially consists of akneadable mixture of malt flour and water. Preferably, the ratios ofmalt flour to water, the consistency of the dough and/or the presence ofadditives are as defined above.

In principle, any cereal type is suitable to serve as raw material for adough according to the invention. Preferably, the dough is based on maltflour of wheat and/or barley, more preferably barley malt flour is oneof the ingredients in the dough.

The invention further relates to a mixture, in particular a dispersion,of malt in water, which mixture is obtainable by means of a methodaccording to the invention.

The invention also relates to a beverage, in particular beer, which isobtainable by means of a method according to the invention.

1. A method for preparing a beverage, wherein a dough—which has beenprepared from malt flour and water—is kneaded and thereafter dilutedwith water to a mixture of malt flour in water, the diluted mixturecontaining 11 to 45 wt. % malt flour, based on the total weight of themixture.
 2. A method according to claim 1, wherein the mixture of maltflour in water is filtered and/or extracted.
 3. A method according toclaim 1, wherein the dough has a consistency of at least 100 BrabenderFarinograph units.
 4. A method according to claim 1, wherein the doughis kneaded for at least 15 min, preferably 30-45 min.
 5. A methodaccording to claim 1, wherein the kneading energy supplied duringkneading is at least 1 kJ/kg malt flour.
 6. A method according to claim1, wherein the dough is kneaded until the supplied energy is 10-100kJ/kg malt flour.
 7. A method according to claim 1, wherein the dough iskneaded at a temperature of 15-50° C., preferably of 20-45° C.
 8. Amethod according to any one of the preceding claims claim 1, wherein themalt flour comprises barley malt flour, wheat malt flour or acombination thereof.
 9. A method according to claim 8, wherein the maltflour has been prepared from an amount of barley which substantiallyconsists of glassy grains, non-germinated grains and/or incompletelygerminated grains.
 10. A method according to claim 1, wherein thebeverage is a fermented beverage, preferably beer. 11-15. (canceled) 16.A method according to claim 2, wherein the dough has a consistency of atleast 100 Brabender Farinograph units.
 17. A method according to claim2, wherein the dough is kneaded for at least 15 min, preferably 30-45min.
 18. A method according to claim 3, wherein the dough is kneaded forat least 15 min, preferably 30-45 min.
 19. A method according to claim2, wherein the kneading energy supplied during kneading is at least 1kJ/kg malt flour.
 20. A method according to claim 3, wherein thekneading energy supplied during kneading is at least 1 kJ/kg malt flour.21. A method according to claim 4, wherein the kneading energy suppliedduring kneading is at least 1 kJ/kg malt flour.
 22. A method accordingto claim 2, wherein the dough is kneaded until the supplied energy is10-100 kJ/kg malt flour.
 23. A method according to claim 3, wherein thedough is kneaded until the supplied energy is 10-100 kJ/kg malt flour.24. A method according to claim 4, wherein the dough is kneaded untilthe supplied energy is 10-100 kJ/kg malt flour.
 25. A method accordingto claim 5, wherein the dough is kneaded until the supplied energy is10-100 kJ/kg malt flour.